DNA Scaffolds with Manganese Oxide/Oxyhydroxide Nanoparticles for Highly Stable Supercapacitance Electrodes

• Published in: ACS applied nano materials Vol. 5; no. 7; pp. 8902 - 8912
• Main Authors: Komarala, Eswaravara Prasadarao, Neethinathan, Clament Sagaya Selvam, Kokkiligadda, Samanth, Mariyappan, Karthikeyan, Yoo, Seong Soo, Yoo, Pil Jin, Park, Sung Ha
• Format: Journal Article
• Language: English
• Published: American Chemical Society 22-07-2022
• Subjects: galvanostatic charge−discharge cycles; supercapacitance activity; cyclic voltammetry; DNA; electrochemical impedance; manganese oxide/oxyhydroxide nanoparticles
• ISSN: 2574-0970; 2574-0970
• DOI: 10.1021/acsanm.2c01091

The utilization of manganese oxides/oxyhydroxides as efficient supercapacitor electrode materials is limited by their cyclic stability and thus restricted for practical applications. One attractive approach for improving their stable electrochemical performance is to form a hybrid with suitable support materials. Herein, we describe the fabrication of manganese oxide/oxyhydroxide nanoparticle (MONP)-embedded deoxyribonucleic acid (DNA) scaffolds using a simple magnetic stirring and drop-casting method. The physical and chemical property measurements provided information regarding the interactions of the MONPs with the DNA in the scaffolds. Further, these materials’ electrical properties were studied by looking at the MONP concentration-dependent current characteristics. Our testing shows a monotonic increase in current with increasing MONP concentration. The supercapacitance activity of MONP-embedded DNA scaffolds with various MONP concentrations was explored using cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) measurements. From the electrochemical studies conducted, it was found that the supercapacitance values achieved while using scaffolds decreased up to a certain concentration of MONPs and then increased thereafter. The DNA scaffolds with a 0.5 weight percentage (wt %) of MONPs achieved ∼60% of the specific capacitance value of pristine MONPs. Long-term cyclic stability studies showed that using pristine MONPs, DNA, and MONP-embedded DNA scaffolds led to the supercapacitor samples retaining 71.9, 104.6, and 108.8%, respectively, of their initial specific capacitance values after 10 000 cycles at a current density of 5 A g–1. The excellent cyclic stability of the devices with DNA-based scaffolds proves that DNA acts as a strong support material and helps to solve one of the major drawbacks of manganese-based supercapacitance electrode materials. This unique approach of utilizing DNA as a stable support material can be extended to numerous other materials to achieve better cyclic stability and can be used for a wide range of electrochemical applications.